Automatic steering apparatus



July 19, 1932., M. G. E. KNIGHT 1,868,360

AUTOMATIC STEERING APPARATUS Filed Jan. 4, 1932 2 Sheets-Sheet l 1f fry July 19, 1932. --M. G. E. KNIGHT AUTOMATIC STEERING APPARATUS Filed Jan. 4, 1952 2 Sheets-Sheet o N i. M'GZTA/N/GHT attorney Patented July 19, 1932 UNITED STATES PATENT OFFICE MAURICE GIBBONS EAGLE KNIGHT, OF GLAREMONT, HOBART, TASMANIA, AUSTRALIA AUTOMATIC STEERING AIPARATUS Application filed January 4, 1932, Serial No. 584,682, and in Australia December 31, 1930.

This invention is directed to an improved guiding mechanism for automatically steering a tractor or engine driven plow or the like through the use of a suitable guide furrow, in order that the subsequent operatlonof the machine, particularly in its proper guiding function, will be automatically controlled.

The primary object of the present invention is the provision of means which will cooperate with an initially formed guide furrow and in such cooperation control, through suitable hydraulic and electric mechanism, the guiding of the machine in accordance with such guide furrow, whereby if a guide furrow is formed to define the outline of the particular field, the machine forming the subsequent furrows will be automatically caused to follow the guide furrow or subsequent furrows until the plowing or other treatment'of the field is completed. V

A further object of the invention is the provision of a guiding element which directly cooperates with the furrow and controls a switch designed to energize steering control mechanism and through such energization govern the steering of the vehicle or implement.

The invention is illustrated in the accompanying drawings, wherein Figure l is a perspective view of the invention showing the same in applied position for use.

Figure 2 is a perspective view of a steering knuckle illustrating particularly the means of attachment of the present invention.

Figure 3 is a perspective view of the steering gear illustrating particularly an electric motor drive.

Figure 4 is a more or less diagrammatic view with parts in plan, and parts in section, showing electric and hydraulic control means in accordance with the present invention, together with the guiding element.

1 Figure 5 is a diagrammatic view of an electric motor for steering control under the influence of the mechanism illustrated in Figure 1.

The invention as illustrated is directed to a bar 2 secured in any appropriate manner at projects forwardly of the tractor and in advance of the wheel is connected to a lateral member 3 having a bearing 4 in the form of a sleeve projecting above and below the memher and at right angles thereto. A spindle 5 is supported in a bearing sleeve 4 for free rotary and vertical movement, a collar 6d adjustable through the medium of a set screw .6?) being arranged on the spindle to limit the downward movement of the spindle in the sleeve bearing l. The spindle 5 is yieldingly held at the downward limit of movement permitted by the collar 6a through the medium of a spring arranged on the spindle below the member 3. The springfia limits the relative upward movement of the spindle and also functions as a buffer in such upward movement.

An arm 10 is, through the medium of a clamp plate 10?), adjustably secured near the upper end of the spindle. A plate 10a is secured to and depends from the upper end of the spindle, being formed with a plurality of openings for the adjustable reception of a hook to which the upper end of a coiled spring 11 is secured. The lower end of the coiled spring is connected to an extension of a yoke-like member forming a control guide 7, the arms of which are connected by a pivot pin 6 arranged to pass through the outturned lower end of the spindle 5. The control guide 7 is made up of a yoke member, on the free ends of the arms of which are slidably secured legs 8, the lower or free ends of which are outturned. The slidable relation of the legs 8 to the yoke member provides for the adjustment of the length of the control guide openings in the legs and in the arms of the yoke member being designed to be connected by a through pin to provide for adjustably con- 95 Eecting the legs to the arms of the yoke mem- The outturned free ends of the legs 8 constitute the ground engaging elements for initially inaugurating the steering operation of the vehicle, and obviously these free terminals of the arms or legs are held in contact with the ground under a yielding pressure through the influence of the spring 11. As the control guide is turned in one direction or the other '2. One end'of the lever carries a pin 17 7 operating through a slot in the box and engaging a switch arm 19 for the electrical control ofthesteering mechanism according to the movement of the lever 15 in response to the actuation of the spindle 5 through the 'medium of the, guide-control including the yoke 7 and the legs 8. The steering elements 1 1 may be governed electrically or hydraulical- 1y, with the hydraulic mechanism electrically controlled.

With more-particular reference to Figure .4, it will be noted that the switch lever 19 operates over a dielectric base 93 arranged in the box 18 and between contacts 21'and 22. The switch lever 19 is in circuit with a battery 24 through the medium ofconductor 19a. The contact 21 is in circuit with a relav 25 and the armature controlled by this relay governs a circuit including a solenoid 26 having an. electromagnet 28 and a movable armature 27.

The switch contact 22 is in circuit with the relay 54, the armature controlled bv which governs a circuit including a solenoid 37 havin: an electro-magnet 39'and an armature 38,

A valve mechanism is arranged intermediate the solenoids26 and 37 including a casing 33 having an exhaust port 34, inlets 41 and 2 leadingfrom a pump having inlet and. outlet valves 44 and 45 and a piston 46 operated by a crank or other driver 47. the pump acting through a conventional pressure reservoir 143. I g

Arranged in'the valve cylinder 33 is a valve rod 31 connected to the respective armatures '27 and 38 of the solenoids 26 and 37. and on i the valve rod is arranged valves-32 and 35 controlling outlet nipes '48 and 49 leading from the valve cylinder .and obviously, ac

cording to the solenoid actuated, placing a particular outlet pipe in communication with .aninlet pipe from the pump, while at the same time the other outlet pipe is placed in communication with the exhaust 34. a The outlet pipes 48 and 49 are so arranged that they may be placed in communication through the medium of-a control valve 50, such outlet .pipes, however, communicating directly, with indicated.

the respective ends of a power cylinder 51 Within which is'arranged a piston 52 connected to a piston rod 53.

Springs 29 and 36 are arranged between the respective armatures 27 and 38 and the ends of the valve cylinder 33 to assist in valve rod movement. A pressure adjustment chamber 144 is in communication with the pump cylinder and with a pressure equalizing cylinder 143. This pressure equalizing chamber has an exhaust pipe 145' and a release valve 146, the latter being connected through the medium of a spring 147 with a hand wheel controlled adjusting rod. The control of the valve 146 obviously controls pump pressure.

The piston rod 53 may be connected in any suitable manner for the actuation of the steering mechanism (not shown) so that in movement of the piston rod in one direction, steering of the tractor will follow in a predetermined direction, the opposite steering of-the tractor being accomplished by the movement of the piston rod in the opposite direction. Thus, if the switch 19 is turned in one direction, the appropriate solenoid is energized and the armature thereof actuated and theval've rod moved with the valves to admit fluid pressure from the pump to one side or the other of the piston 52 and so automatically steer the vehiole. Of course, this steering operation is maintained as long as the circuit is maintained, so thatthe turning or steering move mentis incldent to the closing of the appropriate circuits and the latter directly governed by the guide control, as previously The inlet pipes 41 and 42 from the pump communicate with a pipe 148 which termihates in a jet 149 in a pressure cylinder 150 provided with a manually controlled release valve 151. The release valve is operated by a lever 152 having a steering controlled lever 154 through an intermediate wire connection 153. The lever 154 is connected, in any appropriate manner with the steering gear of the tractor so that the release valve is actuated only when the steering gear has moved to the extreme limit position in either direction. An auxiliary. cylinderl55 is in communication with the cylinder 150 and has arranged therein a "piston 156 through which is connected a piston rod 157,. the piston being spring pressed in one direction by a spring 158. tractor is controlled in the movement of the piston rod 157. l Vhen the steering gear of the tractor is turned to its extreme position,

vlave 151 is opened and the pressure in. cylinder 150 thereby slowly reduced, the re duction, however, being greater than the increase of such pressure possible through the pressure in the jet. 149. Therefore, if

the steering gear remains at. the extreme limit for a comparatively long time, the

Theignition circuit of the Gil pressure in cylinder 155 is so reduced that the spring 158 acts to move the piston 156 'in a direction to cause the piston rod 15? to break the connection between the spaced points 159 of the ignition system, the operation being carried out by moving a bridging bar 159a through the medium of hook elements 160a on the piston rod 157 and on the bridging bar. The book elements, of course, may be disconnected, if desired, manually to prevent any control of the ignition circuit or connected to provide for the automatic control of the ignition circuit to stop the tractor when the. latter has been deflected to one or the other steering limits for too long a period. Thus the automatic ignition control will stop the tractor if the latter leaves the course of the guide furrow entirely, though obviously when extreme steering results from turning a sharp cornor, the valve 151 will naturally be opened before the period is too short to permit a suflicient reduction of pressure in the oylin ders to insure operation of the bridging bar to break the ignition circuit.

In Figure 5 is shown diagrammatically an electric motor adapted to be mounted upon or adjacent to the steering column of the tractor and to be connected thereto by the toothed wheels 160161 (Figure or by any other suitable means. This electri cal apparatus includes a contact lever 19 intermediately pivoted at 20 and opposite contacts 21 and 22, dielectric 23 and battery 24 as before described. The motor is indicated at 55, the poles thereof at 56, the armature at 57 and commutator at 58. Re lays are indicated at 59 and 60, the whole being wired so that the motor is operated by the battery current to correct the steering through any suitable gearing, such as the toothed pinion 161 mounted upon the shaft of the motor and the spur wheel 160 mounted upon the steering column of the tractor (Figure 3), immediately the contact lever 19 makes contact with either of the contacts 21 or 22. In both Figures 4t and 5, the wiring carrying the main current is shown in heavy lines, while the wiring carrying the small relay operating current is shown in fine lines.

lVhen the steering wheels of the tractor aredeflected to either the right or the left, the movement is communicated to the control guide 7 and the switch lever 19 is operated. The lever by making contact completes a circuit and permits the current from the battery to energize the relative relay, thereby closing its contacts and energizing the electro-magnet of the relative solenoid, thereby attracting its armature and moving the pistons 32 and 35 along the cylinder 33. Obviously, when the piston 32, for example, is moved to the left by energization of the solenoid 37, the right inlet pipe 11 and transfer transfer pipes 19 are in communication with the exhaust port 3%, thereby permitting discharge from the cylinder 51 of the fluid displaced by the piston 52. The exhaust fluid may be returned to a supply vessel or tank (not shown) and from which the pump cylinder receives or draws its supply. By means of the valve 50, the right and left transfer pipes 18 and 49 are placed in communication, and operation of the piston 52 neutralized. It will be obvious that the pressure in the reservoir 1 13 may be regulated by the valve 1 161 l7. Pressure in the cylinder 150 is increased under the control of the jet 1 19.

The present invention avoids the disadvantages of a wheel which, for example, tends to continue on in a straight line when subjected to deviation, and it also avoids the comparatively slow movement of such arrangements and, further, avoids imposing any material resistance to movement of the guiding device by reason of connecting links and gearing which themselves receive resistance from the steering wheels or gear of the tractor. The guiding device hereinbefore described is very sensitive in its action and moves freely in the guide furrow. This is essential, particularly in sandy soil and the like and when using a shallow groove or guide furrow.

Further, the present invention does not attempt to manipulate the steering wheels or gear of a tractor directly from the control guide device by links, gearing and the like, but employs the said device to manipulate or cause substantially an immediate operation of effective intermediate apparatus which possesses or develops sufficient power to at once correct the steering of the tractor without conveying or imposing the burden to or upon the control guide. Such apparatus may be of an electric, hydraulic, pneumatic or like nature. By use of the present invention, a field may he completely ploughed without an attendant to or upon the tractor, and it considered that this result is achieved by reason of the sensitiveness of the control guide device which turns under very slight and almost imperceptible side draft or pressure, and also by the provision of such means as will at once release or apply to the steering gear of the tractor power suflicient to align the tractor with the guide furrow very quickly.

I claim:

1. Improvements in or relating to automatic steering apparatus for tractors drawing ploughs or the like, consisting in an hydraulic device adapted to control and/or correct the steering geariof the tractor, means for electrically operating the hydraulic device, and a sensitive, control guide device adapted 'to move along a guide furrow and adapted to operate the electrical means synchronously with deviating movement of the said control guide device in the said guide furrow;

2. Improvements in or relating to automatic steering apparatus for tractors drawing ploughs or the like, consisting in an hydraulic device adapted to control and/or correct the steering gear of the tractor means for electrically operating the hydraulic device, a sensitive control guide device adapted to move along a guide furrow and adapted to operate the electrical means synchronously with deviating movement of the said control guide device in the guide furrow, and means for stopping the tractor should it depart from the guide furrow line.

3. Improvements in or relating to automatic steering apparatus for tractors drawing ploughs or thelike, consisting in a pump, an hydraulic device adapted to control and/or correct the steering gear of the tractor, means for electrically controlling the pressure supply from the pump to the hydraulic control means, a switch controlling the electrical means, and a sensitive control guide device adapted to move along a guide furrow and adapted to operate the switch synchronously with deviating movement of the said guide device in the guide furrow.

tnlrnprovements in or relating to automatic steering apparatus for tractors draW- ing ploughs or the like, consisting in a pump,

an hydraulic device adapted to control and/or correct the steering gear of the tractor, means for electrically controlling the pressure supply from the pump to the hy draulic control means, means for varying the pressure of the hydraulic supply when the steering gear of the tractor is turned to its extreme position, means for stopping the tractor after a predetermined reduction of pressurehas occurred, a switch controlling the electrical means, and a sensitive control guide device adapted to move along a guide furrow and adapted to operate the switch synchronously with deviating movement of the said guide device in the guide furrow.

In'witness whereof I have signed this specification.

MAURICE GIBBONS EAGLE KNIGHT. 

